Micaël BEDIKOU - Academia.edu (original) (raw)

Papers by Micaël BEDIKOU

International Journal of Biological and Chemical Sciences, Nov 8, 2019

In Côte d'Ivoire, the larvae of the oil palm weevil, Rhynchophorus phoenicis, are appreciated and... more In Côte d'Ivoire, the larvae of the oil palm weevil, Rhynchophorus phoenicis, are appreciated and consumed by rural and urban populations. However, many people are unaware of the nutritional qualities of these larvae. The objective of this study was to compare the nutritional value of these larvae with that of the beef and fish usually consumed. The different nutritional components of late stage larvae, beef and fish were determined from standard analytical methods. Moisture contents of 25.66 ± 0.05; 60.47 ± 0.08 and 39 ± 0.28 mg / 100 g, lipid 39.14 ± 0.01; 12.47 ± 0.05 and 1.26 ± 0.005 mg / 100 and protein of 29.9 ± 0.11; 25.56 ± 0.02 and 22.16 ± 0.15 mg / 100 g were obtained for R. phoenicis, beef and fish, respectively. The ash content was 5.02 ± 0.01; 1.5 ± 0.1 and 0.46 ± 0.57 mg / 100 respectively for R. phoenicis, beef and fish. These three samples are characterised by respective iodine numbers of 161.86 ± 0.1; 142.83 ± 0.2 and 45.5 ± 0.4 I2 / 100 g and saponification of 159.53 ± 0.61; 69.33 ± 0.00 mg KOH / g. Larvae, beef and fish oils have acid values of 3.06 ± 0.01; 6.43 ± 0.05 and 6.33 ± 0.057 KOH / g and peroxides 4.56 ± 0.11; 8.56 ± 0.16 and 7.03 ± 0.05 meq O 2 / kg low. This study shows that late stage R.phoenicis larvae have significant nutrients that are able to balance diets.

Food Science and Technology International, Jan 23, 2013

The search for new sources of oil with improved characteristics has focused our attention on the ... more The search for new sources of oil with improved characteristics has focused our attention on the characterisation of Irvingia gabonensis seed kernel oil. Physicochemical analysis have revealed the following assets: refractive index (1.42 ± 0.00), free fatty acids (2.3 ± 0.8%), peroxide value (3.33 ± 0.57 meq O2/kg), iodine value (32.43 ± 1.22 g I2/100 g), saponification value (233.75 ± 2.60 mg KOH/g), unsaponifiable matter (1.5 ± 0.02%), carotenoids (63 ± 0.01 mg β-carotene/100 g) and phospholipids (2.1 ± 0.01%). Absorbance of this oil decreased abruptly in the range of UV-B and UV-A wavelengths. Gas chromatography analysis showed that the major fatty acids were saturated, being mainly composed of lauric (C12:0, 39.35 ± 0.01%) and myristic acids (C14:0, 20.54 ± 0.01%). Nevertheless, an unusually high amount (6.44 ± 0.02%) of linolenic acid was also noted. Mass spectrometer analysis of volatile compounds highlighted the presence of various aromatic and aliphatic organic compounds. I. gabonensis seed kernel oil also showed oxidative stability at 60 °C after 12 days of storage with maximum peroxide value of 34.66 meq O2/kg. In view of these interesting characteristics, I. gabonensis seed kernel could be used as an alternative source of oil for lipid industries.

The International Journal of Plant, Animal and Environmental Sciences, 2014

In tropical Africa where the daily diet is dominated by starchy staples, African leafy vegetables... more In tropical Africa where the daily diet is dominated by starchy staples, African leafy vegetables (ALVs) are the cheapest and most readily available sources of proteins, vitamins, minerals and essential amino acids. Five leafy vegetable species (Amaranthus hybridus, Andasonia digitata, Ceiba patendra, Hibiscus sabdariffa and Vigna unguiculata) that are used as soup condiments in Northern Côte d'Ivoire were subjected to cooking in order to evaluate the effect of this processing method on their nutritive value and antioxidant properties. The result of the study revealed that longer time of cooking (higher than 15 min) caused negative impact by reducing nutritive value but positive impact by reducing anti-nutrients such as oxalates and phytates. The registered losses at 15 min were as follow: ash (9.41-62.87 %), proteins (11.33-36.24 %), vitamin C (33.33-82.14 %), carotenoids (69.17-100%), oxalates (27.23-59.10%) and phytates (40.29-91.03%).The average reduction at 15 min of cooking was 31.30-56.02 % for polyphenols content. Contrary to these reductions, a slight increase of fibres content was observed in the studied cooked leafy vegetables. Furthermore after 15 min, the residual contents of minerals were: calcium (139.10-314.46 mg/100g), magnesium (40.55-344.57 mg/100g), phosphorus (120.46-248.93 mg/100g), potassium (177.65-747.28 mg/100g), iron (18.62-34.31 mg/100g) and zinc (7.33-26.33 mg/100g). All these results suggest that the recommended time of domestic cooking must be less than 15 min for the studied leafy vegetables in order to contribute efficiently to the nutritional requirement and to the food security of Ivorian population.

European Journal of Entomology, May 20, 2009

An extracellular-mannosidase with unusual properties was purified from the digestive fluid of oil... more An extracellular-mannosidase with unusual properties was purified from the digestive fluid of oil palm weevil (Rhynchophorus palmarum Linnaeus) larvae using ammonium sulphate saturation, size exclusion and anion-exchange chromatography. The enzyme named RpltM is thermoacidophilic, thermostable and behaves like lysosomal-mannosidase (EC 3.2.1.24). The molecular weight, Km value, optimum reaction temperature and pH are 108-112 kDa, 0.36 mM, 65°C and 4.5, respectively. Zn 2+ enhanced whereas Cu 2+ , Sodium dodecyl sulphate, swainsonine and 1,4-dideoxy-1,4-iminomannitol strongly inhibited its hydrolytic activity. The enzyme was stable for 25 min at 65°C and retained 70% of its initial activity after 60 min. At 70°C, around 60% of this activity was conserved after 25 min. RpltM retained more than 90% of its activity over a pH range of 4.2 to 5.0 and remained fully active in the presence of detergents such as nonidet P-40, triton X-100, polyoxyethylen-10-oleyl ether (up to 1%, w/v), dithiothreitol and-mercaptoethanol. The stability under these conditions is also better than that reported for other insect-mannosidases. Thus, RpltM could be used as an important bioindustrial tool for removing mannose residues from oligosaccharides.

Tropical Journal of Pharmaceutical Research, Oct 10, 2012

Purpose: To investigate the seed oils of Corchorus olitorius and Hibiscus sabdariffa for their an... more Purpose: To investigate the seed oils of Corchorus olitorius and Hibiscus sabdariffa for their antioxidant and antimicrobial potential. Methods: The physicochemical characteristics of oil of the plant seeds were determined using standard methods while their volatile compounds were analyzed by gas chromatography coupled with mass spectrometery (GC-MS). The antioxidant activity of these oils was determined using 2,2-Diphenyl-1picrylhydrazyl (DPPH) free radical scavenging method, and their antimicrobial effect was determined by agar dilution method. Results: Phospholipids, carotenoids and phenols contents of the studied seed oils were approximately 2.0 %, 100 mg/100g and 6.7 mg/100g, respectively. GC-MS analysis of the volatile compounds showed the presence of various aromatic and aliphatic organic compounds while the antioxidant activity of the oils was in the range of 0 to 5 g/l, which was higher than that of ascorbic acid. The seed oils also showed antimicrobial activity against Staphylococcus aureus, Aspergillus fumigatus and Trichophyton mentagrophytes with minimal inhibitory concentrations (MIC) of 250.0 and 62.5 mg/ml for C. olitorius and H. sabdariffa seed oils, respectively. Conclusion: C. olitorius and H. sabdariffa seed oils showed pronounced antioxidant and antimicrobial activities. These characteristics should be exploited for possible applications in the food supplement, pharmaceutical and cosmetic industries.

The aim of this study is to gain understanding of the of the potential of local cereal flours in ... more The aim of this study is to gain understanding of the of the potential of local cereal flours in an urban context and the segment of the urban population concerned with traditional dishes made thereof In Cote d’Ivoire cereals are produced in the northern areas where they are traditionally consumed. These local cereals concerns: rice, maize, sorghum, millet and fonio. This survey showed that only maize along with millet flours were in greatest demand among the consumers in the districts of Abidjan (p<0.05). Ash-containing yellow maize and pure white maize flours are commonly consumed. The consumers surveyed, all ethnic groups combined, preferred white maize and millet flours more than yellow maize flour according to the Pearson Chi2 test (p<0.05). Millet flour is predominantly cooked in the form of thin porridge, while the main form of preparing white and yellow maize flours is a dense paste (to) eaten wit...

Biotechnology Journal International, 2017

Aims: Microbial enzymatic activities are important in cassava dough fermentation for attiéké prod... more Aims: Microbial enzymatic activities are important in cassava dough fermentation for attiéké production. The objective of this study was to describe the molecular identification and the amylolytic, pectinolytic and cellulolytic enzymes potential of four (4) Bacillus species involved in cassava mash fermentation for the preparation of attiéké.

European Scientific Journal, Aug 30, 2014

In Côte d'Ivoire, cereals are traditionally grown in northern areas. After production, they are g... more In Côte d'Ivoire, cereals are traditionally grown in northern areas. After production, they are generally transformed into flours and consumed mainly as staple foods in form of thin and thick porridges or alcoholic or non-alcoholic beverages. However, constraints to traditional processing of local cereals have led to a shift towards adoption of quality, easy to cook imported cereal products. Mechanization of the hulling and milling steps for flours production has become a way to valorize local cereals. This survey help assert that millet and maize flours were the main local cereal flours produced and sold on the markets. No significant difference was found between the numbers of women processors of millet, white and yellow maize flours identified (P<0.05). Preference between the local cereal flours showed that on a 1 to 3 scale comparison (P<0.05), millet flour ranked as being the most prized followed by white maize and then yellow maize. The yellow maize owes its popularity to addition of alkaline ash. In terms of volumes of production and sale, maize flours were the most important (P<0.05). As far as quality was concerned, the wet processing and the ignorance of hygiene practices observed are limiting factors.

SpringerPlus, 2014

The enzymatic and acid hydrolysis have converted eight new starches into a range of chain lengths... more The enzymatic and acid hydrolysis have converted eight new starches into a range of chain lengths mainly including glucose, maltose, and maltodextrins as observed on TLC plates, irrespective to the starch variety and treatment. Results of the enzymatic hydrolysis have highlighted the possibility of the use of V 4 and V 64 , which can be labelled as "dietary fibres", to enhance the organoleptic qualities of foods and for fibre fortification of low-calorie products. Concerning V 66 and V 69 , they have much relevant in food, textile and pharmaceutical applications. The acid hydrolysis showed that V 73 is the best starch in the chemical industry for making environment-friendly products such as plastics. Because starch is a natural component that degrade quickly in normal composting condition, the whole studied starches could be advised for various utilizations in the food, textile, paper, biofuel, pharmaceutical and plastic industries for sustainable development.

Sciences & Nature, 2010

In Sub-Saharan Africa, Lagenaria siceraria is an oleaginous cucurbit widely consumed for its edib... more In Sub-Saharan Africa, Lagenaria siceraria is an oleaginous cucurbit widely consumed for its edible seeds. These seeds were previously categorized as good enzyme sources, including four non-specific acid phosphatases isolated and designated as BLsAP1, BLsAP2, RLsAP1, and RLsAP2. In this study, we investigate on the kinetic and thermodynamic characteristics of these biocatalysts in order to evaluate their thermostability. Thermal inactivation was carried out in the temperature range of 55°C to 80°C from 5 to 60 minutes. The results revealed that thermal inactivation of studied acid phosphatases follows first order kinetics. At their optimum temperatures, these enzymes showed high half-lives ranging from 169.06 to 495.10 minutes and D values from 561.71 to 1,645.03 minutes. Moreover, they exhibited high activation energies (from 155.08 to 200.55 kJ/mol) and average enthalpy values (from 152.23 to 197.74 kJ.mol −1) suggesting their good thermostability. The comparison of all these values revealed that the two acid phosphatases (RLsAP1 and RLsAP2) from the round-fruited cultivar of L. siceraria showed better thermal stability than those (BLsAP1 and BLsAP2) from the blocky-fruited cultivar.

Tropical Journal of Pharmaceutical Research, 2012

Food Science and Technology International, 2013

Bulletin of …, 2009

Three extracellular α-mannosidases (EC 3.2. 1.24) were purified from the digestive fluid of oil p... more Three extracellular α-mannosidases (EC 3.2. 1.24) were purified from the digestive fluid of oil palm weevil larvae, Rhynchophorus palmarum (L.) and characterized in order to explore their potential for biotechnological application. Three steps procedure including ...

Applied Biochemistry and Biotechnology, 2009

Two biological fluids, namely hemolymph and digestive fluid from the larval stage of Rhynchophoru... more Two biological fluids, namely hemolymph and digestive fluid from the larval stage of Rhynchophorus palmarum Linneaus, a serious pest in agroecosystem exploiting oil palm, were screened for hydrolytic activities, by the use of synthetic and natural glycoside substrates. Several exo and endoglycosidase activities were observed but, the interesting α-mannosidase activity (0.41±0.04 UI) had attracted our attention. So, we have previously demonstrated that this activity harbours four distinctive α-mannosidase isoforms named RpltM, RplM1, RplM2 and RplM3. We have extended this work to determine the ability of these enzymes to catalyze synthesis reactions. Finally, we have revealed that, αmannosidases from the digestive fluid of R. palmarum larvae catalyze transmannosylation reactions. The stability of the enzymes and the optimization of the transfer product yield were studied as functions of pH, enzyme unit, starting concentration of donor or acceptor and time. It was shown that, in experimental optimum conditions, average yields of 12.34± 0.75, 12.15±0.79, 5.59±0.35 and 8.43±0.50% were obtained for the α-mannosidases RpltM, RplM1, RplM2 and RplM3, respectively. On the basis of this work, α-mannosidases from the digestive fluid of Rhynchophorus palmarum larvae appear to be a valuable tool for the preparation of neoglycoconjugates.

Journal of Applied …

Objective: To analyze the enzymatic potential of the seeds of Lagenaria siceraria (round-fruited ... more Objective: To analyze the enzymatic potential of the seeds of Lagenaria siceraria (round-fruited cultivar), an indigenous cucurbit that is an orphan crop, though widely cultivated and distributed in Côte d'Ivoire. Methodology and results: The seeds extract of L. siceraria round-fruited cultivar was screened using a variety of synthetic and natural substrates for hydrolytic enzymes activities. The best enzymatic hydrolysis mainly consisted of phosphatase (0.71 ± 0.02 UI/mg), β-galactosidase (0.31 ± 0.03 UI/mg) and αmannosidase (0.21 ± 0.02 UI/mg) activities. Physicochemical characterization showed that the three enzymatic activities were acidic (pH 4.6-5.6) and mesophilic (55°C). Also, they appeared to be stable in the presence of most cationic, non-ionic and anionic detergents as well as in the presence of cations (Na + , K + , Ca 2+ , Ba 2+ and Mg 2+) assayed. Substrate specificity showed that the seeds extract hydrolyzed a broad range of natural substrates such as adenosine-5'-triphosphate, pyrophosphate, phosphorylated sugars (glucose-1-phosphate, glucose-6-phosphate, fructose-1-phosphate and fructose-6-phosphate), lactose and the three differently linked (α-1,2; α-1,3; α-1,6) mannobioses. Conclusions and potential application of findings: The properties of the three enzymatic activities make them attractive for potential biotechnological applications. More investigations are proposed to characterise them further.

Journal of Animal & …, 2010

Investigation on the enzymatic potential of oleaginous cucurbit (Lagenaria siceraria roundfruited... more Investigation on the enzymatic potential of oleaginous cucurbit (Lagenaria siceraria roundfruited cultivar) seeds led to purification of two acid phosphatases named RLsAP1 and RLsAP2. Properties of these enzymes were examined in order to explore their potential in biotechnology applications. A four steps procedure including, anion and cation exchange, size exclusion and hydrophobic interaction chromatography were used for purification. The enzymes had native molecular weights of approximately 70 and 55 kDa, respectively and functioned both as dimeric structures. The two phosphatases displayed acidic and mesophilic activities by using para-nitrophenylphosphate as a substrate. Their activities were enhanced by Mg 2+ , K + and ethylene diamine tetraacetic acid (EDTA). Substrate specificity indicated that the two enzymes hydrolyzed a broad range of phosphorylated substrates mainly consisting of adenosine-5'-triphosphate (ATP) and adenosine-5'diphosphate (ADP) hydrolysis. Furthermore, the purified acid phosphatase RLsAP1 exhibited an interesting phytasic activity. These results suggest that the two purified acid phosphatases might play an important role in energy transfer, releasing of inorganic phosphate and in reducing the rate of phytate, an antinutrient contained in this plant seeds. RLsAP1 could find potential use in both human food and animal feed.

Native and gelatinized starches from eight improved cassava varieties were extracted and... more Native and gelatinized starches from eight improved cassava varieties were extracted and subjected to enzymatic and acid hydrolysis in order to highlight their potential of industrial application. The enzymatic hydrolysis showed that native starches were less hydrolyzed (8.40–15.80 10 -2 UI/mg of proteins) than the gelatinized ones with values ranged from 1.14.10 2 UI (V 23 ) to 6.93 10 2 UI/mg of proteins (V 54 ). Thin layer chromatography analysis showed glucose and a high molecular mass maltodextrin as the common products released from both starches. Maltose and another low molecular mass maltodextrin were in addition observed when gelatinized starches were used. The hydrochloric acid solution had showed predominant conversion of V 4 , V 54 and V 55 with maximum values of reducing sugar products of about 70, 62, and 82 µmol, respectively. The starch variety V 52 recorded the lowest value (36.23 µmol of reducing sugar). Due to the relat...